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-rw-r--r--kernel/drivers/gpio/gpiolib.h170
1 files changed, 170 insertions, 0 deletions
diff --git a/kernel/drivers/gpio/gpiolib.h b/kernel/drivers/gpio/gpiolib.h
new file mode 100644
index 000000000..594b1798c
--- /dev/null
+++ b/kernel/drivers/gpio/gpiolib.h
@@ -0,0 +1,170 @@
+/*
+ * Internal GPIO functions.
+ *
+ * Copyright (C) 2013, Intel Corporation
+ * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef GPIOLIB_H
+#define GPIOLIB_H
+
+#include <linux/err.h>
+#include <linux/device.h>
+
+enum of_gpio_flags;
+
+struct acpi_device;
+
+/**
+ * struct acpi_gpio_info - ACPI GPIO specific information
+ * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
+ * @active_low: in case of @gpioint, the pin is active low
+ */
+struct acpi_gpio_info {
+ bool gpioint;
+ bool active_low;
+};
+
+/* gpio suffixes used for ACPI and device tree lookup */
+static const char * const gpio_suffixes[] = { "gpios", "gpio" };
+
+#ifdef CONFIG_ACPI
+void acpi_gpiochip_add(struct gpio_chip *chip);
+void acpi_gpiochip_remove(struct gpio_chip *chip);
+
+void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
+void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
+
+struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
+ const char *propname, int index,
+ struct acpi_gpio_info *info);
+
+int acpi_gpio_count(struct device *dev, const char *con_id);
+#else
+static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
+static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
+
+static inline void
+acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
+
+static inline void
+acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
+
+static inline struct gpio_desc *
+acpi_get_gpiod_by_index(struct acpi_device *adev, const char *propname,
+ int index, struct acpi_gpio_info *info)
+{
+ return ERR_PTR(-ENOSYS);
+}
+
+static inline int acpi_gpio_count(struct device *dev, const char *con_id)
+{
+ return -ENODEV;
+}
+#endif
+
+struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
+ const char *list_name, int index, enum of_gpio_flags *flags);
+
+struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
+
+extern struct spinlock gpio_lock;
+extern struct list_head gpio_chips;
+
+struct gpio_desc {
+ struct gpio_chip *chip;
+ unsigned long flags;
+/* flag symbols are bit numbers */
+#define FLAG_REQUESTED 0
+#define FLAG_IS_OUT 1
+#define FLAG_EXPORT 2 /* protected by sysfs_lock */
+#define FLAG_SYSFS 3 /* exported via /sys/class/gpio/control */
+#define FLAG_TRIG_FALL 4 /* trigger on falling edge */
+#define FLAG_TRIG_RISE 5 /* trigger on rising edge */
+#define FLAG_ACTIVE_LOW 6 /* value has active low */
+#define FLAG_OPEN_DRAIN 7 /* Gpio is open drain type */
+#define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */
+#define FLAG_USED_AS_IRQ 9 /* GPIO is connected to an IRQ */
+#define FLAG_SYSFS_DIR 10 /* show sysfs direction attribute */
+#define FLAG_IS_HOGGED 11 /* GPIO is hogged */
+
+#define ID_SHIFT 16 /* add new flags before this one */
+
+#define GPIO_FLAGS_MASK ((1 << ID_SHIFT) - 1)
+#define GPIO_TRIGGER_MASK (BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE))
+
+ const char *label;
+};
+
+int gpiod_request(struct gpio_desc *desc, const char *label);
+void gpiod_free(struct gpio_desc *desc);
+int gpiod_hog(struct gpio_desc *desc, const char *name,
+ unsigned long lflags, enum gpiod_flags dflags);
+
+/*
+ * Return the GPIO number of the passed descriptor relative to its chip
+ */
+static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
+{
+ return desc - &desc->chip->desc[0];
+}
+
+/* With descriptor prefix */
+
+#define gpiod_emerg(desc, fmt, ...) \
+ pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
+ ##__VA_ARGS__)
+#define gpiod_crit(desc, fmt, ...) \
+ pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
+ ##__VA_ARGS__)
+#define gpiod_err(desc, fmt, ...) \
+ pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
+ ##__VA_ARGS__)
+#define gpiod_warn(desc, fmt, ...) \
+ pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
+ ##__VA_ARGS__)
+#define gpiod_info(desc, fmt, ...) \
+ pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
+ ##__VA_ARGS__)
+#define gpiod_dbg(desc, fmt, ...) \
+ pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
+ ##__VA_ARGS__)
+
+/* With chip prefix */
+
+#define chip_emerg(chip, fmt, ...) \
+ pr_emerg("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
+#define chip_crit(chip, fmt, ...) \
+ pr_crit("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
+#define chip_err(chip, fmt, ...) \
+ pr_err("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
+#define chip_warn(chip, fmt, ...) \
+ pr_warn("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
+#define chip_info(chip, fmt, ...) \
+ pr_info("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
+#define chip_dbg(chip, fmt, ...) \
+ pr_debug("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
+
+#ifdef CONFIG_GPIO_SYSFS
+
+int gpiochip_export(struct gpio_chip *chip);
+void gpiochip_unexport(struct gpio_chip *chip);
+
+#else
+
+static inline int gpiochip_export(struct gpio_chip *chip)
+{
+ return 0;
+}
+
+static inline void gpiochip_unexport(struct gpio_chip *chip)
+{
+}
+
+#endif /* CONFIG_GPIO_SYSFS */
+
+#endif /* GPIOLIB_H */